ND (Neutral Density) Filter

NDfiltersreduce the amount of light and colours that enter thelensin equal amounts giving you a greater choice of aperture and shutter speed.  This is particularly useful when trying to achieve slow shutter speed effects during the day or in lighter conditions as the shutter speed can be slowed without over exposing the image.  NDfilterscan be obtained in a number of different ’strengths’ for use in different conditions.

NDfilterscan also be graduated and used for conditions where part of the scene is brighter than others.

An example of how an ND filter can be used is below, the image was taken during the day at a shutter speed of 8 seconds, this would have completely over exposed the photo if the ND filter(s) had not been used.  Using the ‘Cokin’ filter attachment you can also use 1, 2 or even 3 ND filter at once to give greater flexibility of your aperture and shutter speed settings.

IR (Infrared) Filter

An IR filter will block visible light and only allow infrared light to pass through to the cameralens.  The part of the spectrum that infrared uses is referred to as near infrared, this is different from far infrared, which is used inthermal imaging.  Infraredfilterswill turn the sky very dark, greens can appear almost white.  Some excellent examples of Infrared photography can be found in thisgalleryof photos by Allon Kira.

By: Werner Kunz (werkunz1)

Polarizing Filter

A polarizing filter can be used to darken skies increasing the contrast between the clouds and the sky.  Heat haze and reflected sunlight are reduced, and in color photographs saturation is increased. Polarizers can be used when taking images involving reflectadions, such as those of water or glass as the reflections can be reduced.

UV (Ultra Violet) Filter

UVfilters are used to reduce haziness created by ultraviolet light. A UV filter is mostly transparent to visible light, and can be left on thelensfor nearly all shots. A strong UV filter cuts off some visible light in the violet part of the spectrum, and so has a pale yellow color.  Strong UVfiltersare also sometimes used for warming color photos taken in shade with daylight-type film.

ColourFilters

Filters can be purchased in a variety of colours, these can be solid colours or graduated.  Colours such as orange or red can be used to exaggerate the colour in a sunset photo for example whereas blues could be used when taking photos of the sea.  

StarFilters

Star filters(or cross screenfilters) create points of light,  streaking outward from a central source of light.  This can make lighting within the scene take on a more dramatic appearance.  This effect is produced by a series of thin lines etched onto the surface of a clear filter.

Credit: ddamredhead

Credit: ddamredhead

 

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